The standard Windows software clock can be considerably inaccurate.
There are several ways to synchronize one's computer to standard time
(see subsequent question). However, most of these ways require
continuous access to the internet, which may not be the case
at many school sites and in developing nations. The detection
of SIDs and sharing of subsequent data does not require extreme
clock accuracy, so the monitors can still be used in areas
without internet access. However, techniques are available
for those sites interested in keeping a very accurate clock
(see below).